Fixed warnings

Author: yassirbisteni

articles/communication-services/quickstarts/voice-video-calling/includes/pre-call-diagnostics/pre-call-diagnostics-android.md

@@ -11,7 +11,7 @@ ms.topic: conceptual
 ms.service: azure-communication-services
 ---
 
-# Precall diagnostics
+## Precall diagnostics
 
 [!INCLUDE [Public Preview Disclaimer](../../../../includes/public-preview-include.md)]
 

articles/communication-services/quickstarts/voice-video-calling/includes/pre-call-diagnostics/pre-call-diagnostics-ios.md

@@ -11,7 +11,7 @@ ms.topic: conceptual
 ms.service: azure-communication-services
 ---
 
-# Precall diagnostics
+## Precall diagnostics
 
 [!INCLUDE [Public Preview Disclaimer](../../../../includes/public-preview-include.md)]
 

articles/communication-services/quickstarts/voice-video-calling/includes/pre-call-diagnostics/pre-call-diagnostics-javascript.md

@@ -11,7 +11,7 @@ ms.topic: conceptual
 ms.service: azure-communication-services
 ---
 
-# Pre-call diagnostic
+## Precall diagnostics
 
 [!INCLUDE [Public Preview Disclaimer](../../../../includes/public-preview-include.md)]
 

articles/communication-services/quickstarts/voice-video-calling/includes/pre-call-diagnostics/pre-call-diagnostics-windows.md

@@ -11,7 +11,7 @@ ms.topic: conceptual
 ms.service: azure-communication-services
 ---
 
-# Precall diagnostics
+## Precall diagnostics
 
 [!INCLUDE [Public Preview Disclaimer](../../../../includes/public-preview-include.md)]